G99 Managed · Three-Phase

Commercial Solar PV Installation

Solar PV systems designed around your business's actual energy profile. We install for commercial premises, agricultural buildings, industrial rooftops and multi-unit developments across Essex, Suffolk, Norfolk, Cambridgeshire and Hertfordshire.

Why Afta Electrical
Fully CertifiedCommercial installation certification
G99 managedDNO applications handled
Three-phase systemsFor commercial supplies
NAPIT & TrustMarkGovernment-endorsed scheme
Est. 2015Commercial & domestic

About This Service

Solar designed around your business

Commercial solar is fundamentally different from domestic solar — the financial case is driven by self-consumption during business hours, the DNO process is more complex, and the structural and electrical considerations of commercial rooftops require a different level of design work. We approach commercial projects with the same rigour we apply to domestic installations, scaled appropriately.

We install commercial solar systems from 20kW to 250kW across the East of England. Larger projects are assessed on a case-by-case basis and may involve working with specialist structural engineers, planning consultants or multiple DNO connection agreements. We'll tell you at the outset what the project involves and what the realistic timeline looks like.

Business-hours self-consumption

The economics of commercial solar depend almost entirely on daytime self-consumption — how much of what you generate you actually use during business hours, when the premises is occupied and energy demand is highest. For offices, warehouses, manufacturing facilities and farms with daytime energy demand, self-consumption rates of 70–90% are achievable without battery storage. We model your half-hourly consumption data against irradiance data for your specific location before recommending a system size.

G99 DNO process

Commercial systems above 16A per phase (typically above 11kW on single-phase or above 32kW on three-phase) require a G99 application to the Distribution Network Operator. This is a formal engineering assessment that can take 8–26 weeks and may require a protection relay, export limiting, or a dedicated DNO metering arrangement. We manage the full G99 process and build the expected timeline into project planning.

Agricultural and barn roof installations

Agricultural buildings — particularly steel portal frame barns and grain stores — are often ideally suited to solar. Roof areas are large, orientation is often good, and agricultural energy demand (refrigeration, irrigation pumps, lighting, EV charging for farm vehicles) frequently aligns with solar generation periods. We work with farmers and agricultural businesses throughout East Anglia and are familiar with the specific structural and planning requirements that apply.

Zero VAT on commercial solar

Solar PV installations on commercial premises benefit from zero-rate VAT (reduced from 20% in April 2022 for qualifying installations). We'll confirm applicability for your specific project at the survey stage.

Half-hourly consumption modelling

We model your actual energy consumption data against irradiance to size the system correctly — not based on roof area alone.

Full G99 management

DNO application, protection relay specification, metering arrangement and commissioning notification — all handled by us.

Three-phase inverters

Commercial three-phase supplies require three-phase inverters for balanced loading. We specify and install appropriate equipment.

Export limiting available

Where DNOs require export limitation, we install and commission export limiting devices as part of the G99 approval.

Battery storage integration

Commercial battery storage added alongside solar for sites with evening demand or high grid import outside business hours.

What's Included

Every commercial installation includes

Energy & roof survey

Roof structural assessment, orientation and shading analysis, half-hourly consumption data review. Written system design with expected output and financial modelling.

Tier-1 commercial panels

High-efficiency mono PERC or TOPCon panels selected for commercial applications. 25-year performance warranty. Bulk pricing from quantity.

Commercial inverter system

Three-phase string or central inverters. SolarEdge, Solis or Fronius. Sized for three-phase balanced output and G99 compliance.

G99 DNO application

Full G99 submission including protection relay specification where required. Timeline managed proactively. No surprises at commissioning.

Installation & commissioning

Scaffolding or MEWP access, rail mounting, DC cabling, AC distribution, protection devices and metering. DNO commissioning notification submitted on completion.

Installation certificate & handover

Full installation certification on completion. Monitoring platform set up and handed over. As-installed drawings and test certificates provided.

Considering solar for your business or farm?

Send us your latest half-year electricity bill and we'll give you a preliminary output and payback estimate before any site visit commitment.
Request a Commercial Survey

Common Questions

Commercial solar FAQs

What system size is right for my business?
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The right system size is determined by your roof area, orientation, and — most importantly — your daytime electricity consumption. Oversizing beyond your daytime consumption capacity reduces the financial return because export rates are a fraction of import rates. We analyse your actual half-hourly consumption data before recommending a size, and we'll tell you honestly if the roof or DNO constraints limit what's achievable.
How long does a G99 DNO application take?
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G99 applications typically take 8–26 weeks depending on the DNO and the complexity of the connection. UKPN (the DNO for Essex, Hertfordshire and parts of East Anglia) and SSEN (Norfolk and Suffolk) each have their own processes. We submit the application as early as possible in the project and manage the DNO correspondence. The installation itself can often proceed while the G99 is pending, with commissioning deferred until approval is received.
Does a commercial solar system require planning permission?
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Commercial solar installations are not automatically permitted development in the way domestic installations are. Systems up to 1MW may qualify as permitted development under Class J or Class R of the GPDO (Town and Country Planning Act), subject to conditions. Larger systems, installations on listed buildings or buildings in conservation areas, and ground-mounted arrays require full planning consent. We'll advise on planning requirements during the survey and can recommend planning consultants where needed.
Can you install on a metal agricultural building?
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Yes — agricultural buildings with metal profiled roofing (trapezoidal or sinusoidal profiles) are among the most cost-effective commercial solar installations. Rail systems are available for most profile types and fixing is straightforward. We'll assess the roof structure, purlin spacing and condition during the survey to confirm the mounting system and any structural reinforcement requirements.
Is commercial solar eligible for any tax incentives?
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Commercial solar systems can qualify for full expensing (100% first-year capital allowance) under the current HMRC regime, allowing the full cost to be deducted from taxable profit in the year of purchase. This can significantly reduce the effective cost of a commercial installation. We recommend discussing the specific tax treatment with your accountant, as it depends on your business structure and accounting period.
What maintenance does a commercial solar system require?
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Commercial systems benefit from annual performance reviews against generation data, and the inverters should be serviced every 5 years as a minimum. We can provide annual O&M (operations and maintenance) contracts for commercial customers, covering monitoring, annual inspection, inverter servicing, and priority attendance for faults. Maintenance contracts are quoted separately from the installation.

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Free Commercial Solar Survey

Get a tailored quote for your commercial site

Answer 7 quick questions and we'll assess your site's solar potential and come back with a clear, honest proposal. Takes about 2 minutes.

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Question 1 of 7
What type of commercial building is it?
Building type affects system design, planning requirements and DNO process.
Question 2 of 7
What type of roof does the building have?
Roof type determines the mounting system and installation approach.
Question 3 of 7
What is your approximate monthly electricity spend?
This helps us estimate the payback period and right system size for your site.
Question 4 of 7
Are you interested in battery storage alongside solar?
Battery storage can maximise self-use and provide power resilience for commercial premises.
Question 5 of 7
Do you have a DNO or grid connection reference?
For larger systems (>16A/phase), a G99 application to your DNO is required.
Question 6 of 7
When are you looking to proceed?
We can start the design and DNO process in advance of your preferred start date.
Question 7 of 7
Almost done — where shall we send your results?
We'll review your answers and get back to you with honest, tailored advice. No hard sell, no spam.

Thank you — we'll be in touch soon!

We've received your commercial solar survey. One of our specialists will review your answers and come back with a tailored assessment and proposal — usually within two business days.

Commercial energy bills you can
actually control.

We design commercial solar systems around your actual consumption data — not roof area. Send us a recent electricity bill and we'll give you a preliminary assessment before any site visit commitment.

Request a Survey Domestic Solar